In mobile communication networks, when mobile communication equipment has a failure, corresponding alarm information may be generated, so that operation and administration personnel can learn the occurrence of failure and locate and troubleshoot the failure as soon as possible. The alarm information first is sent by a network element to an Element Management System (EMS) through a south bound interface (Itf-S). If a Network Management System (NMS) subscribes related alarms, when a failure occurs, the alarm information may be reported to the NMS from the EMS through the south bound interface. Sometimes, when a failure occurs, a chain reaction may be caused, a plurality of alarms may be generated synchronously and these alarms generally have correlation with each other. Under such circumstance, analysis may be performed using alarm correlation to find the root alarm, so as to reduce the number of alarms actually reported or to accelerate the location of failure. For traditional mobile communication networks, some methods for alarm correlation are already available. However, in the related methods for alarm correlation, when analysing the correlation between alarms, lots of alarms need to be analyzed, causing low alarm analysis efficiency and slow fault location.